Vehicle Propulsion System

ABSTRACT

A vehicle propulsion system has a sealed, closed loop steam generating system connected to supply steam to drive a small turbine that drives an alternator or generator to produce electrical energy that is supplied to electric traction motors at the wheels of the vehicle to propel the vehicle. According to some of the embodiments, a cooling coil is associated with the steam generating system to facilitate complete and rapid condensing of the steam back to water. At least one battery is connected in the system to supply electrical energy during start up and as otherwise needed. A controller such as a CPU or PC Main Board is connected with the propulsion system to regulate and control distribution of electrical energy to components of the system.

NOTICE OF COPYRIGHT PROTECTION

A portion of the disclosure of this patent document and its figures contain material subject to copyright protection. The copyright owner has no objection to the facsimile reproduction by anyone of the patent document or the patent disclosure, but otherwise reserves all copyrights whatsoever.

CO-PENDING, PRIORITY APPLICATION

This application claims priority benefit of Provisional Patent Application, filed Dec. 24, 2009 using U.S. Express Mail No. EH 264 502 076 US and Attorney Docket No. 57595, titled “VEHICLE PROPULSION SYSTEM” having Maurice C. Avery named as the inventor and which Provisional Patent Application is incorporated herein by references as if set forth in full below.

FIELD OF THE INVENTION

This invention relates to a power generating and propulsion system for vehicles, and more particularly, to a system that uses a steam-powered turbine to drive a generator or alternator to produce electricity that is supplied to a drive motor or to electric traction motors.

BACKGROUND OF THE INVENTION

Nearly all automobiles sold for the past seven decades have been powered by internal combustion engines, primarily of the reciprocating piston variety. However, in the early days of the automobile, particularly up until the introduction of the electric starter by Cadillac in 1912, automobiles were more commonly powered by steam or electricity than by gasoline-powered combustion engines. Up until introduction of the electric starter, internal combustion engines relied on a hand crank to start the engine, which was difficult and occasionally dangerous to use, as improper cranking could cause a backfire capable of breaking the arm of the operator. Electric cars were popular to some extent, but had a short range, and could not be charged on the road if the batteries ran low.

A significant benefit of the steam engine is that the fuel burner can be configured for very low emissions of carbon monoxide, nitrogen oxides and unburned carbon in the exhaust, thus avoiding or minimizing pollution. It can use virtually any type of fuel and is exceptionally quiet in operation. A clutch or transmission is not required because of the substantial torque produced from rpm. The output of the engine typically is geared directly to the rear axle of the vehicle.

However, early steam cars could take over a minute to start from cold, plus time to get the burner to operating temperature. Further, steam engines used in early steam cars were so-called open steam systems wherein the exhaust steam was vented directly to the atmosphere. This required carrying large quantities of water and/or frequent refilling of the water tank. Early steam cars typically had a range of only 20 to 50 miles. Moreover, these early steam systems required large heavy boilers and large capacity vapor systems, thereby decreasing the power-to-weight ratio and reducing the amount of usable space in the vehicle. The large boilers also increased the amount of time required to heat the water to a usable state.

The Model B Doble steam car solved some of the problems of early steam cars by incorporating a steam condenser which enabled the water supply to last for as much as 1,500 miles instead of the 20 to 50 mile range of the typical steam car. Start-up time was also shortened considerably by incorporating a highly efficient monotube steam generator to heat a much smaller quantity of water, along with effective automation of burner and water feed control. By 1923, Doble's Steam cars could be started from cold with the turn of a key and driven off in 40 seconds or less.

In spite of the advances made in the Doble steam car, the time required to build up steam from a cold boiler was perhaps one of the main reasons steam power systems never achieved wide-spread continuous use in automobiles. The introduction of the electric starter, and assembly-line mass production by Henry Ford, which hugely reduced the cost of owning a conventional automobile, were also strong factors in the demise of the steam car.

A great amount of time and research has been expended in recent years to develop hybrid and electric vehicles, and alternate fuels such as biodiesel, ethanol, hydrogen, and compressed and liquefied natural gas.

Efforts also have been made in recent years to develop and reintroduce the steam engine as a motive power means for automobiles. The biggest arguments in favor of such a movement are the practically nil discharge of pollutants, silence in operation, and direct drive without need for a gearbox.

U.S. Pat. Nos. 3,339,663, 4,119,861, 4,951,769, 5,385,211, 5,522,723, 6,508,060, 6,397,962, 6,829,894, 7,314,104, and published U.S. Patent Application Ser. No. 2002/0153178 disclose examples of steam generating means and/or vehicle drive systems that rely in various ways on steam power. Additional examples of recent efforts include the Saab Steam Car and the Pelland Steamer in 1974, and, commencing in 1996, the Enginion Steamcell and British Steam Car.

The Saab steam car engine used an electronically controlled 28 pound multi-parallel-circuit steam generator with 1 millimeter bore tubing and 16 gallons per hour firing rate which was intended to produce 160 hp, and was about the same size as a standard car battery. Lengthy start-up times were avoided by using air compressed and stored when the car was running to power the cars upon starting until adequate steam pressure was built up. The engine used a conical rotary valve made from pure boron nitride. To conserve water, a hermetically sealed water system was used.

The Pelland Steamer had a fiberglass monocoque chassis and used a twin-cylinder double-acting compound engine. In 1977 the Pelland Mk II Steam Car had a three-cylinder double-acting engine in a “broad arrow” configuration, mounted in a tubular steel chassis with a Kevlar body, giving a gross weight of just 1,050 lb. This engine was claimed to give trouble-free, efficient performance. It had huge torque (1,100 ft-lb) at zero engine rpm, and could accelerate from 0 to 60 mph in under 8 seconds.

The Enginion Steam cell, see U.S. Pat. Nos. 5,522,723, 6,508,060 and 6,829,894, developed by Enginion AG, an R&D subsidiary of the Volkswagen group, had a system called ZEE (Zero Emissions Engine). It produced steam almost instantly without an open flame, and took 30 seconds to reach maximum power from a cold start. A third prototype, the EZEE03, was a three-cylinder unit described as having a “two-stroke” (i.e., single-acting) engine of 1000 cc (61 cubic inch) displacement, producing up to 220 hp (500 N-m or 369 ft-lbf). Exhaust emissions were said to be far below the Super Ultra Low Emission Vehicle (SULEV) standard, which is a U.S. classification for conventionally powered or gasoline-electric hybrid vehicles designed to produce minimal air pollution at their point of use, typically 90% less than that of an equivalent ordinary full gasoline vehicle. It had an “oilless” engine with ceramic cylinder linings using steam instead of oil as a lubricant.

The British Steam Car uses compressed-air-powered hydraulics to inject distilled water and pre-prime itself. The water is pumped into the start of 1.86 miles of tubing to develop three megawatts of heat to convert water into 750 F steam. This super-heated “dry” steam is then directed down the car via heavily lagged pipes and two enormous industrial steam valves, which act as throttles, and then into the two-stage turbine. The steam is injected into the turbine at over two times the speed of sound. The turbine spins at up to 13,000 rpm and drives the rear wheels via a conventional crown wheel and pinion. The vehicle turns 10.5 gallons of water a minute into super-heated steam at 40 times atmospheric pressure. The steam is not condensed and is exhausted to atmosphere.

SUMMARY

The present invention comprises a steam generating system for vehicles, wherein steam produced in a boiler (e.g., a flash boiler) or other high efficiency steam producing device is used to drive a turbine that in turn drives a generator or alternator to produce electricity that is supplied to electric traction motors at the wheels of the vehicle to propel the vehicle. Alternatively, the power from the generator or alternator may be supplied to a drive motor to the wheels.

The steam generating system is a sealed closed loop and requires no or minimal make-up water. Further, a small refrigeration system (e.g., cooling turbine) is associated with the condenser to facilitate complete and rapid condensing of the steam back to water and condition it for maximum expansion in the boiler when it is again converted to steam.

According to an exemplary embodiment, the power means for the vehicle comprises electric motors at the wheels, and the steam is used to drive a small main drive turbine that operates an alternator for supplying electrical energy to the motor(s). Boiling of the water to produce steam occurs quickly and the system has minimal weight and occupies minimal space, adding to the overall efficiency of the vehicle.

One or more batteries are connected in the system to supply electrical energy during start up and for other uses as needed. After start up, electrical energy for the system is supplied by the alternator or alternatively, by a generator.

Electrical energy developed by the battery and generator or alternator is supplied to a controller which regulates and controls the distribution of electrical energy to the traction motors or to drive motor(s), to the ignition system for the burner in the boiler, to recharge the battery, and to other auxiliary systems and devices as needed.

DESCRIPTION OF THE DRAWINGS

The foregoing, as well as other objects and advantages of the invention, will become apparent from the following detailed description when taken in conjunction with the accompanying drawings, wherein like reference characters designate like parts throughout the several views, and wherein:

FIG. 1 is a schematic diagram of the basic components of the system according to exemplary embodiments of the invention.

FIG. 2 is a schematic block diagram of the steam generating and electrical supply systems according to exemplary embodiments of the invention.

FIG. 3 is a schematic block diagram of an alternate steam generating and electrical supply systems according to exemplary embodiments of the invention.

DESCRIPTION OF THE INVENTION

The word “exemplary” is used herein to mean “serving as an example, instance, or illustration.” Any configuration or design described herein as “exemplary” is not necessarily to be construed as preferred or advantageous over other configurations or designs.

This invention now will be described more fully hereinafter with reference to the accompanying drawings, in which exemplary embodiments are shown. This invention may, however, be embodied in many different forms and should not be construed as limited to the embodiments set forth herein. Moreover, all statements herein reciting embodiments of the invention, as well as specific examples thereof, are intended to encompass both structural and functional equivalents thereof. Additionally, it is intended that such equivalents include both currently known equivalents as well as equivalents developed in the future (i.e., any elements developed that perform the same function, regardless of structure).

Thus, for example, it will be appreciated by those of ordinary skill in the art that the diagrams, schematics, illustrations, and the like represent conceptual views or perspective views illustrating some of this invention. The functions of the various elements shown in the figures may vary in shape, attachment, size, and other physical features. Those of ordinary skill in the art further understand that the exemplary systems, and/or methods described herein are for illustrative purposes and, thus, are not intended to be limited to any particular named manufacturer or other relevant physical limitation (e.g., material, such as metal, ceramic, other man-made products, natural materials, and combinations thereof).

Referring more specifically to the drawings, a basic vehicle drive system according to exemplary embodiments of the invention is indicated generally at 10 in FIG. 1. In FIG. 1, a steam system II for producing high pressure steam is connected to supply steam to a turbine 12 which drives an alternator or generator 13 to produce electrical energy that is supplied to a controller 14 to regulate and distribute the electrical energy to traction motors 15 at the wheels of the vehicle. The controller 14 is also connected with a battery 16 to receive electrical energy from the battery and distribute it to the system as needed, such as, for example, during start up or to recharge the battery from energy supplied by the alternator or generator when the system is running). The controller 14 can include a CPU or Main PC Board (shown as reference numeral 314 in FIG. 3) and be constructed to function generally like conventional computerized engine control systems—that is, to control the operation of vehicle components and accessories such as various sensors, lights, electric windows, door locks, audio equipment, and the like. The controller also includes circuitry for controlling devices such as a breaking system, traction control, active handling, components of the engine, and the like. According to some of the embodiments, the vehicle uses electric (dynamic) braking for light stopping needs and conventional hydraulic ABS braking for other stopping rates. The controller can be programmed to control the supply of electrical energy to the motors 15 so that they are all uniformly driven, or they can be driven unequally, or one or more of them can be driven while brakes are applied to one or more others. As shown in the particular embodiment illustrated, a foot pedal 16 is used to adjust the controller to vary the energy supplied to the motors and thus vary the acceleration of the vehicle.

Additional details of the steam system 11 of FIG. 1 are shown in FIG. 2. As seen in FIG. 2, the steam system comprises a flash boiler 20 and super heater header 21 connected in a sealed closed loop 22 with the turbine 12 and a condenser 23. A fuel supply 24 and fuel pump 25 are connected with the burner (shown as reference numeral 302 in FIG. 3) in the boiler to supply fuel to the burner as needed. An important part of the invention is the small refrigeration system 26 associated with the condenser 23 to facilitate rapid condensing of the steam to liquid form for return to the boiler. In the exemplary embodiments shown in FIGS. 1 and 2, the refrigeration system includes a compressor 27, expansion valve 28, and coil 29 disposed around the conduit that returns the condensate to the boiler.

A small reservoir 30 of make up water and an associated water pump, 31, can be connected with the boiler if desired, although it is contemplated that the sealed closed loop system will not require the addition of make up water during normal operation between service intervals. Further, if deemed necessary, an expansion tank 32 and one-way valve 33 can be connected with the boiler, and a pump 34 can be incorporated in the return conduit to return the condensate to the boiler.

The boiler can be of any desired design, although a flash boiler or other highly efficient boiler is preferred. U.S. Pat. No. 3,635,284 discloses an exemplary flash boiler design that could be used or modified for use in the system of this invention shown in FIG. 2, and the disclosure of that patent is incorporated in full herein by reference. Another possible heater for use in the exemplary embodiments of FIGS. 1 and 2 is the heater disclosed in U.S. Pat. No. 5,522,723, and the disclosure of that patent is incorporated in full herein by reference.

Essentially, the '723 patent discloses a Caloric Porous Structure Cell (CPSC), an aluminum oxide-based ceramic heat cell that can theoretically process any fuel that can be vaporized and pre-mixed with air while producing extremely low emissions. The pores of the cell structure are designed in such a way that the fuel is prevented from flaming up, which would produce spikes in emissions of hydrocarbons (HC), carbon monoxide (CO), and nitrous oxides (NOx). The developer of the CPSC claims that hydrocarbon emissions cannot be detected, that carbon monoxide and nitrous oxide emissions are well below 10 parts per million, and that the latest cell designs cut these levels by 50%. Adding exhaust gas recirculation reduces them even further. The even combustion process also keeps the cell at a “moderate” 1200 F, and the manufacturer claims that the cell's power output can be varied from 5%-100% of its rated output of 30 MW/m3, and has a response time of just 5 milliseconds. A glow plug is used to start the cell. However, one of ordinary skill in the art appreciates that the battery of the present invention could be of sufficient amp/hour capacity to immediately propel the vehicle from a “cold” start until a head of steam is generated.

Microwave or ultrasonic energy might also be used to boil the water in the boiler. See U.S. Pat. No. 6,397,962, the disclosure of which is incorporated in full herein by reference.

U.S. Pat. No. 6,829,894 discloses a steam system that incorporates features to prevent freezing and damage to the system in cold climates, and the disclosure of that patent is incorporated in full herein by reference. The Equal Zero Emission Engine (EZEE) has an insulated water tank, to prevent damage in freezing conditions. Also, once the freezing point is reached a small flame is ignited to keep the temperature in the tank at 5° C. This heating mechanism is shut down after several weeks have passed in order to conserve energy, and the water tank has been designed to take the pressure exerted by the freezing water without cracking. The manufacturer claims it takes an engine 30 seconds to reach maximum power from a cold start, though the car can drive away before then. This compares favorably with the time needed to accomplish a similar task with a diesel engine. The CPSC can burn gasoline, diesel, kerosene, natural gas, alcohol, methane, hydrogen, or other renewable fuels. It does not use an open flame, which drastically reduces emissions of NOx and CO. If any hydrocarbon emissions are produced, they are beyond measurement, pursuant to claims of the manufacturer.

Referring now to FIG. 3, an alternate steam generating system is shown. The fuel is conveyed from its naturally pressured storage container 301 through an emergency shutoff valve. This shutoff valve is controlled by a Main PC Board 314 (e.g., upon sensing an over temperature, over pressure or over speed condition from various sensors in the system. The emergency shutoff is energized closed until the fault condition has cleared).

A primary heat exchanger 302 fires and commences generating stem when the ignition switch (not shown) is turned on and the accelerator position sensor or accelerator pedal is depressed for desired vehicle motion. Main batteries 316 provide the vehicle motion during the period that the boiler (shown as reference numerals 302 and 303) is building the necessary “head” of steam.

All electrical power to drive one or more main drive motors 313—whether solely from the main batteries 316 or from the alternator 309 (e.g., when an on-speed steam generated condition exists) will pass through an inverter 312 that in turn, delivers power to the main drive motor 313. Power to the motor is regulated by a silicon-controlled rectifier that receives load requirements based on the position of the accelerator position sensor.

As adequate steam is produced, it passes through a pressure/flow control valve 305 and on through to a main drive turbine 306. The pressure/flow control valve 305 regulates as needed to maintain a desired set rpm of the main drive turbine 306. According to some of the embodiments, the set rpm is 6 rpm. RPM sensing can be either in a reduction gear box or at the alternator. RPM signals are sent to the Main PC Board 314 which in turns sends a control signal to the pressure/flow control valve 305 for the proper positioning to maintain necessary steam delivery to the turbine 306.

The “spent” steam that exits the main turbine 306 still contains a certain amount of heat and uncondensed steam, and therefore, is passed into a cooling turbine 307. The gases (chilled/condensed) exiting the cooling turbine 307 are capable of dropping below 30 F thereby freezing the condensed water vapor on its way to a water separator 319 (or water collector). The flow of gas through the cooling turbine is the opposite of a turbine that compresses a gas as it flows through it. In the case of a cooling turbine, the gas is suddenly decompressed to lower the temperature. Although water is disclosed, one of ordinary skill in the art appreciates that alternate substances or mixtures may be used to change properties of the matter used to go from a liquid state to a gaseous state back to a liquid state.

A temperature sensor 317 is electrically tiled to the Main PC Board 314 to send a signal to a mixing valve 308 to inject system steam from the boiler to maintain the cooling turbine 307 outlet temperatures just above freezing.

A pressure sensor 318 (preferably mounted on a high pressure steam circuit leading to the main turbine 306) is electrically tied to the Main PC Board 314 which in turn sends a signal that regulates the boiler burner valve fuel delivery rate.

As water is returned to its condensed state at the water separator/collector 319, it is pumped to a secondary heat exchanger 303 of the boiler where it is preheated to around 100 to 125 F. A float level sensor (not shown) in the secondary heat exchanger 303 energizes a high pressure pump 311 to supply preheated water to the primary heat exchanger 302 of the boiler. The pump 311 is able to overcome primary heat exchanger operating pressures. As one of ordinary skill in the art recognizes, the excess heat remaining after exiting the secondary heat exchanger is drawn through a heat exchanger (air to air) to provide passenger heat.

Since the main drive turbine 306 is regulated at speeds of around 20,000 to 30,000 rpm, the alternator 309 does not need to turn as fast. A reduction gear 322 provides a mechanical advantage to the turbine. The alternator load is regulated by the Main PC Board 314 by varying the field current to the alternator based on battery charge needs and system loads to propel the vehicle and power other electrical demands of the vehicle. The batteries 316 are of sufficient amp/hour rating to propel the vehicle while a “head” of steam is building in the boiler.

An A/C to D/C converter 320 and a back up charging plug 321 may be added as an alternative to charging the batteries 316, such as, via an A/C outlet of a building, such as the vehicle owner's home.

According to some of the embodiments, the secondary heat exchanger of FIG. 3 in the boiler is utilized to extract some of the “waste” heat from the primary heat exchanger. The “waste” heat is used to pre-heat the condensed water being pumped from the water separator. In order to produce steam, the exhaust gas temperature exiting the primary heat exchanger must be a temperature above the boiling point of water's boiling point, and thus, the “excess” exhaust gas temperature may be used to pre-heat the water. The closer the exhaust temperature leaving the draft inducer is to ambient, the more efficient the boiler. Thus, the “draft inducer” is employed. The “draft inducer” is a blower (e.g., squirrel cage) that is drawing the combustion air into the primary burner and pushing the exhaust gases out (e.g., out of a tail pipe). As appreciated by one of ordinary skill in the art, “draft inducers” allow all or most of the heat energy to be extracted from the burner.

The main drive turbine 306, cooling turbine 307, reduction gear box 322, and alternator 309 are regulated at a constant rpm. The Main PC Board adjusts the field load to the alternator as system loads demand. Simultaneously, the Main PC Board adjusts the gas valve burn rate as needed to maintain the required steam “load” to the turbine.

While the invention has been particularly shown and described with references to a preferred embodiment thereof, it will be understood by those skilled in the art that various changes in form and details may be made therein without departing from the spirit and scope of the invention. 

1. A vehicle propulsion system, comprising: a sealed, closed loop steam generating system carried by the vehicle, said steam generating system including a boiler for converting water from its liquid state to its steam vapor state, and a condenser for condensing the vapor state back to the liquid state; a small turbine connected to be driven by steam produced by the steam generating system; electricity producing means connected to be driven by the turbine; at least one electric motor connected to drive means of the vehicle to propel the vehicle when electricity produced by the electricity producing means is supplied to said at least one electric motor; a small refrigeration system associated with the condenser to facilitate complete and rapid condensing of the steam back to water and condition it for maximum expansion in the boiler when it is again converted to steam; at least one battery connected in the system to supply electrical energy during start up; and a controller connected with the propulsion system to regulate and control distribution of electrical energy to said at least one electric motor, to the refrigeration system, to the boiler, and to recharge the battery.
 2. A vehicle drive system as claimed in claim 1, wherein: the boiler comprises a Hash boiler and super heater header.
 3. A vehicle drive system as claimed in claim 2, wherein: the boiler comprises a caloric porous structure cell.
 4. A vehicle drive system as claimed in claim 2, wherein: the small refrigeration system comprises a compressor, an expansion valve, and a coil, said coil being disposed in heat exchange relationship with condensed steam returning from the condenser to the boiler.
 5. A vehicle drive system as claimed in claim 4, wherein: the vehicle is a wheeled vehicle; and said at least one electric motor comprises an electric traction motor connected to drive at least one wheel of the vehicle. 